Method of forming workpieces



Allg- 11 1964 c. E. BAWTINHEIMER 3,143,901

METHOD OF FORM-ING WORKPIECES V Original Filed July 18, 1958 2Sheets-Sheet 1 0 :if N :"5 s 9 mi f m .Q Y i s: i n g i m P E, ai I.

INVENTOR CHAPAES E BWYNHUMER Aug. 11, 1964 c. E. BAwTlNHElMER 3,143,901

METHOD oF FORMING woRKPIEcEs Original Filed July 18. 1958 2 Sheets-Sheet2 INVENTOR.

CHARLES E EA\NT\N\\\E\MER.

w3 BY United States Patent O 3,143,901 METHD @Il FRMING WORKPIECESCharles E., liawtinheimer, 2805 Ronan St., Midland, Mich. Originalapplication .Iuly 1S, 1958, Ser. No. 749,496, now

Patent No. 3,023,647, dated Mar. 6, 1962. and this appiication Sept. 27,1961, Ser. No. 141,126

3 Claims. (Cl. 77-32.2)

This application is a division of copending application Serial No.749,496, filed July 18, 1958, now Patent No. 3,023,647.

This invention relates to a method of forming workpieces in strictaccordance with a preformed model or pattern and more particularly theinvention pertains to a method of drilling finger holes in bowling ballsat such locations and of such configuration that the drilled holes willconform to the span and normal curvature of the users fingers.

Most of the bowling balls currently in use are provided with fingerholes which are drilled straight into the ball and with diameters toaccommodate the thumb and one or more other lingers of a users hand.Bowling balls formed in this manner are rather difficult to use with anygreat degree of control inasmuch as the ball must be supported solely bythe pressure exerted by squeezing the thumb and fingers towards oneanother. The difiiculties inherent in bowling balls formed in thedescribed manner have been recognized heretofore and various proposalshave been made to overcome them. For example, it has been proposed thatrubber or the like pads be inserted in the finger holes to provide for amore secure grip and some of these pads have been ,shaped to approximatethe curvature of the users fingers. More frequently, the bowling ballusers will coat their fingers with a chalk or rosin substance whereasothers attempt to obtain a form-fitting grip by whittling the fingerholes in a bowling ball. It also has been proposed to form the fingerholes of a bowling ball along the arc of a circle, thereby approximatingto some extent the natural curvature of a users fingers. The difficultywith this particular construction, however, is that it, like thestraight hole method, forms holes in a bowling ball which onlyapproximate the spacing or span of a prospective users fingers.

Ideally, a bowling ball should have its linger holes spaced according tothe spacing of the intended users fingers and of a diameter toaccommodate the fingers freely, and the holes should be formed on acurvature corresponding to the natural curvature of the users fingers.Such a bowling ball naturally would fit the users hand better, provide abetter grip, and enable the user to have more control over the ballinasmuch as there would be less chance of the ball slipping from hisgrasp prior to the time he intended to release it.

An object of this invention is to provide a method of forming fingerholes in the bowling ball and which are so located and contoured as tocorrespond to the `s pacing and natural configuration of a usersfingers.

A further object of the invention is to provide a method of forming aworkpiece such as a bowling ball in strict accordance with a preformedpattern or model.

Other objects and advantages of the invention will be pointed outspecifically or will become apparent from the following description whenit is considered in conjunction with the appended claims and theaccompanying drawings, in which:V Y

FIGURE 1 is a fragmentary, diagrammatic view illustrating the manner offorming finger holes in a pattern or model bowling ball;

FIGURE 2 is a fragmentary side-elevational view of apparatus formed inaccordance with the invention;

FIGURE 3 is an enlarged, fragmentary, partly sec- Divided 3,143,901Patented Aug. 11, 1964 tional view of a portion of the apparatus shownin FIG- URE 2;

FIGURE 4 is an enlarged, fragmentary, front elevational view of a detailof the apparatus shown in FIG- URE 2;

FIGURE 5 is a partly sectional view of a bowling ball formed inaccordance with the invention;

FIGURE 6 is a wiring diagram for a portion of the apparatus; and

FIGURE 7 is a wiring diagram for another part of the apparatus.

Apparatus suitable for practicing the method of the invention isillustrated in FIGURE 2 as comprising a base 1 having its upper surfaceslotted as at 2 to receive a slide 3 which is slideable back and vforthin a horizontal plane between dovetail guides 4 provided on the base.The supporting plate 3 is of less width than the base 1 and may besecured in a selected position of adjustment relative to the base 1 bymeans of a number of set screws 5, two of which are shown in FIGURE 2.Connected by means of bolts 6 to opposite ends of the 'base 1 are twopairs of supporting arms 7, each of the supporting arms been providedwith axles or shafts 8 on which are rotatably journaled rollers 9, therollers on each of the arms 7 being vertically spaced from one another.Above the level of the base 1 is located a supporting plate 11 having alaterally extending flange 12 at its opposite ends which is receivedbetween the rollers 9 so as to be supported thereby for to and fromovements in a horizontal plane parallel to the plane of movement of theslide 3.

Adjacent to each of the four corners of the slide 3 is provided ajournal block 13 in which is rotatably mounted a shaft 14 which isthreaded at its upper end as indicated at 15. The upper, threaded end ofeach of the shafts 14 extends through a threaded opening formed in amounting platform 16, and each of the projecting ends of the shafts 14is provided with a sprocket wheel 17 around which is trained a sprocketchain 18. The platform 16 is so mounted that it is horizontal, but iscapable of movement in a vertical plane upon rotation of the shafts 14.

Means is provided for rotating the shafts 14 and comprises an electricmotor 19 which may be mounted on the slide 3 adjacent one of the shafts14. The armature shaft 26 of the motor has fixed thereto a bevel gear 21which meshes with a similar gear 22 fixed on the adjacent shaft 14. Thearrangement is such that operation of the motor 19 will cause rotationof the adjacent shaft 14 and the rotation of the one shaft 14 will betransmitted to each of the others via the sprocket wheels 17 and thechains 18 so as to cause movement of the platform 16 up or down,depending on the direction of drive of the motor 19.

The mounting platform 16 is provided with a pair of `openings in each ofwhich is fixed a bushing 23 by means of which a pair of shafts 24 and 25are rotatably supported on the platform 16. Each of the shafts 24 and 25may carry at its upper end a sprocket wheel 26 and 27, respectively,around which is trained a sprocket chain 28, and the shaft 25 may beprovided with a bevel gear 29 fixed at its upper end in a position tomesh with a similar gear 30 fixed to the armature shaft 31 of anelectric motor 32 supported on the platform 16.` The arrangement is suchthat operation of the motor 32 will cause rotation of the shaft 25 androtation of the latter shaft will be transmitted to the shaft 24 via thesprocket wheels 26, 27 and the chain 28.

Fixed to the lower end of the shaft 2S is a yoke 33 (see FIGURE 4)having a pair of spaced apart arms 34, each of which is provided withan-opening adapted t0 receive a stub shaft 35. Corresponding ends ofeach stub shaft 35 are fixed to a mounting harness 36 comprising 'a pairof spaced side arms 37 interconnected at corresponding ends by atransverse bar 3S and being rigidly connected at their opposite ends toa plate 39 having a centrally located opening 40 therein. The distancebetween the plate 39 and the transverse bar 38 is such as toaccommodatea workpiece such as a bowling ball blank B therebetween, but thediameter of the opening 4Q is less than the diameter of the blank B soas to prevent the latter from falling through the opening. The crossbar38 of the harness is provided with a threaded opening through whichextends a threaded shaft 41 having a clamping block 42 at its lower endshaped to correspond to the curvature f the blank B and adapted to bearagainst the latter to clamp the blank firmly in the plate opening 40.The upper end of the shaft 41 may be provided with a crank or handle 43to facilitate turning the shaft.

The connection of the harness 36 to the yoke 33 is such that the harnessand the blank carried thereby are rotatable about a horizontal axiscorresponding to the axis of the stub shafts 35. In order to determinethe angular position of the harness, one of the shafts 35 may have fixedthereto a protractor 44 having a scale 45 inscribed thereon adapted tobe read in conjunction with a pointer 46 fixed on the adjacent yoke arm34. To x the harness in a selected position of adjustment, the arm 34 ofthe yoke may be provided with a brackett 47 in which is adjustablymounted a set screw 48 that is adapted to bear against the protractor44.

The shaft 24 is provided with a pattern or model supporting apparatussimilar to the workpiece supporting apparatus just described andcorresponding elements of the model supporting apparatus are numberedthe same as the elements of the workpiece supporting apparatus, butfollowed by the letter a. The difference between the two supportingdevices is that the stub shafts 35a, instead of being fixed to a harnesssuch as the harness 36, may be screwed or otherwise secured to amounting board or panel 148 on which a model or pattern M is secured.The described mounting means for the blank and model harnesses are suchthat both the model and the blank are capable of conjoint, universalmovement.

The model or pattern M comprises a hemispherical mass of initiallyworkable but hardenable material such as wax, putty, plaster of Paris,or the like, which may be clamped or fixed in any suitable manner to themounting board 148. To form the model, the mass of material, in asemiplastic state, is supported on a table 49 or the like and the userfor whom a bowling ball is to be made inserts a desired number of hislingers into the mass to form finger holes therein. The user works hisfingers in the mass to form holes of the desired shape and configurationand conforming substantially to the normal span and configuration of theusers fingers. Thereafter, the mass of material may be permitted toharden, whereupon the model M may be supported on its supportingapparatus in the manner shown in FIGURE 2.

On the upper surface of the supporting plate 11 is fixed a pair ofmounting brackets 51 and 52, the spacing between them correspondingsubstantially to the spacing between the shafts 24 and 2S. On thebracket 51 is supported an electric motor 52a having leads 53 and 54connected through a switch (not shown) to a suitable source of electricenergy. The armature shaft 55 of the motor is directed upwardly towardsthe bowling ball blank B and is fitted at its upper end with a cuttingtool 56 of a suitable kind capable of boring into the blank. On thebracket 52 is fixed in any suitable manner a tab or ear 57 to which ispivotally connected, by means of a pin 58, one end of a feeler orfollower device 59. The device 59 comprises a rod 60 which receives atits upper end a socket member 61 formed at the lower end of a knob 62the same size and shape as the tool 56. At the base of the socket formedin the socket member 61 is a normally closed switch having blades 63 and64 and adapted to be opened upon telescoping movement of the arm 6d andthe socket member 61 by engagement with a post 65 formed at the upperend of the arm 60 and projecting towards the switch blade 63. The blade63 and the post 65 normally are maintained out of engagement by means ofa spring 66 which is interposed between the upper end of the arm 60 andthe base of the socket formed in the socket member 61.

Also mounted on the supporting bracket 52 is a vertical post 67 to whichis secured one end of a tension spring 68, the other end of the latterbeing fastened to an eye 69 fixed on the rod 60. The arrangement is suchthat the follower device normally is urged to rock about the axis of thepin 58 in a clockwise direction, as viewed in FIG- URE 2, and the extentof clockwise rocking movement of the device 59 is limited by a stopmember 70 mounted on the bracket 52 in a position between the device 59and the post 67.

As has been pointed out earlier, the supporting plate 11 is mounted forto and fro movement between the several pairs of rollers 9. Means isprovided for effecting to and fro movements of the member 11 and theparts supported thereby and comprises a reversible, D.C. motor 71mounted on the base 1 and having its armature shaft 72 connected to acoupling 73 which also is connected to a driving shaft 74 forming partof a gear reduction mechanism 75 of known construction and supportedalso on the base 1. The gear reduction mechanism includes a driven shaft76 which is threaded as indicated at 77 and which extends through athreaded opening 78 formed in the supporting member 11. The arrangementis such that operation of the motor 71 will cause the supporting plate11 and its associated parts to be moved to the left or to the right, asviewed in FIGURE 2, depending upon the direction of rotation of themotor.

The apparatus includes means for actuating the motor 71 and preferablycomprises a light reflective device such as a mirror 79 rigidlyconnected to the follower arm 60 and arranged to receive a beam of lightdirected from a lamp 80 or similar device through a lens 81 and reflectit in the geenral direction of a pair of spaced apart photoelectriccells 82 and 83. The construction and arrangement of the motor actuatingmechanism are such that, when the follower device 59 is in a verticalposition, the light beam reflected by the mirror 79 passes between thephotoelectric cells 82 and 83 so that no more light falls on one than onthe other.

The photoelectric cells 82 and 83 form part of a circuit illustrated inFIGURE 6. Other elements of the circuit include a pair of triodeelectron tubes 84 and 84a and the motor 71. The circuit derives itsenergy from one or more transformers, preferably one, but for purposesof illustration the circuit is disclosed as including four primarytransformer windings P-l, P-2, P-3 and P-4. Associated with the primarywinding P-1 is a secondary winding S-1 connected at one of its ends to awire 85 which is connected to one of the terminals of the photoelectriccell 82 and also to one of the terminals of the motor 71. The otherterminal of the transformer winding S-1 is connected through a resistorS6 to a line 37 which is connected to the other terminal of thephotoelectric cell 82 and to the grid 88 of the triode 84. The plate 89of the tube 84 is connected by a wire 90 to one side of a secondarywinding S-2 associated with the primary winding P-2, the other side ofthe winding S-Z being connected to a wire 91 which leads to one end of asecondary winding S-3 and which also is connected to one terminal of thephotoelectric cell 83, the cathode 92 of the tube 84a, and to theremaining terminal of the motor 71. From the other terminal of thesecondary Winding S-3 extends a line 93 which is connected through aresistor 94vto a terminal of the photoelectric cell 83 and to the grid95 of the tube 84a. The plate 96 of the tube 84a is connected by a wire97 to one terminal of the secondary winding S-4, the other terminal ofwhich is` connected to the Wire 85. The wire 85, as is shown in FIGURE6, also is connected to the cathode 92a of the tube 84. The terminals ofthe motor 71 are bridged by a wire 98 in which is located a capacitor99. Also included as part of the electrical circuit shown in FIG- URE 6is a constantly excited field winding 100 for the D.C. motor 71. Theapparatus shown in FIGURE 6 is essentially Va pair of interconnectedrectifier circuits arranged to balance one another except during certainconditions yet to be explained. If necessary or desired, suitableamplification stages may be incorporated in the circuit between thephotocells and the motor 71.

Another part of the electrical apparatus is disclosed in FIGURE 7 ascomprising a wire 101 leading from the motor 19 through a push buttonswitch 102 to a source of energy such as 110 volt A.C. From the otherterminal of the motor 19 leads a wire 103 which is connected to themovable switch blade 63 to the source of energy.

To condition the apparatus for operation, the model M having preformedfinger openings 50 therein is mounted on the stub shafts 35a of themodel supporting shaft 24. Thereafter, the slide 3, the supporting plate11, the supporting platform 16 and the backing member 148 are adjustedrelatively to one another so that the knob 62 of the follower device 59enters one of the preformed finger openings 50 and bears against one ofthe walls of the opening in such manner that the arm 60 is located in avertical position. Simultaneously, the bowling ball blank B is insertedin its harness 36 and the latter adjusted to the same angularity as themodel mounting plate 148, as is determined by the positions of theprotractors 45 and 45a. In these conditions of the parts, the cuttingtool 56 will be in a position to bear against the surface of the blank Bto bore an opening in the latter.

When the apparatus has been conditioned in the manner described, themotor 52a may be started to drive the cutting tool 56. As the cutting ofthe blank B progresses, the push button 102 may be actuated by themachine operator to cause the motor 19 to turn the shafts 14 in suchdirection as to cause the platform 16 to lower, thereby feeding theblank B to the cutting tool 56. As long as the follower arm 60 is in avertical position, light reflected from the lamp 80 will pass betweenthe photoelectric cells 82 and 83, energizing neither of them, with theresult that, at any given instant, the grid of one triode tube 84 willbe biased negatively and its plate positively, whereas the grid of theother triode tube will be biased positively and its plate biasednegatively. As a result, the motor '71 is in a condition of electricalbalance and no movement of the mounting plate 11 takes place. As theplatform 16 is lowered, however, the wall of the finger opening whichreceives the knob 62 will fall away from the latter, thereby enablingthe spring 68 to swing the arm about the axis of the pivot pin 58. Asthe arm swings, the mirror '79 also will swing so as to refiect lightfrom the lamp Si) to one or the other of the photoelectric cells S2 and83, thereby energizing the affected cell and completing a circuit to themotor 71 to cause it to drive the mounting plate 11 and its associatedparts in one direction or the other tending to restore the arm 60 to itsvertical position. As a result, the knob 62 of the follower device 59will be enabled to follow the contour of the finger opening 50 and sincethe motor 52a follows the movements of the mounting plate 11, theopening Stia drilled in the bowling ball blank will conform to thepreformed opening 50 in the model M. As the drilling operation of theblank B proceeds, the motor 32 may be operated so as slowly to causerotation of the blank B and the model M about the axes of theirrespective shafts 25 and 24. Rotation of the shafts 24 and 25 willassure reproduction in the blank B of the holes formed in the model.

' such that the knob `62 of the follower device 59 engages the base ofthe opening 50 in the model, further lowering movement of the platform16 will compress the spring 66 interposed between the arm 60 and thesocket part 61 so as to enable the projection 65 to engage the springswitch arm 63 and open the switch, thereby causing operation of themotor 19 to cease. Thereafter, the motor 19 may be operated in thereverse direction to withdraw the model and the blank in a directionaway from the mounting plate 11 so as to free the follower device andthecutting tool from the bores of their respective holes.

When one of the holes 50a has been formed in the blank B, the model Mmay be readjusted relative to the follower device S9, and the blank Badjusted an equal amount to the cutting tool S6, so as to effect thecutting of a second opening 50a in the blank B corresponding to a secondopening 50 in the model M. This procedure may be repeated for as manyfinger openings as are to be formed in the blank B. Ultimately, abowling ball such as is shown in FIGURE 5 will be formed with fingeropenings 50a conforming exactly to the openings 5t) which were preformedin the model M. In this connection, it is not necessary to conform tothe configuration of the users fingers those regions of the finger holeswhich would be adjacent the back of the users lingers when the ball isin use, inasmuch as these regions of the finger holes are not in contactwith the users fingers. Accordingly, whenever reference to conformationof the finger holes to a users fingers is made, it is intended to referto those portions of the finger holes which would lie adjacent the innersurfaces of the users fingers. However, it is not intended to limit theinvention to conforming only the inner portions of the finger holes tothe users fingers, as the holes may be formed in such manner as toapproximate the shapes of the users fingers.

-The disclosed embodiment is representative of a presently preferredmethod according to the invention, but is intended to be illustrativerather than definitive thereof. The invention is defined in the claims.

I claim:

l. The method of cutting curved finger openings in a bowling ball blankin accordance with the natural span and curvature of the prospectiveusers fingers, said method comprising the steps of forming a mass ofmaterial in a semiplastic state to simulate a bowling ball; insertingthe prospective users fingers in said material to form curved fingeropenings therein; mounting said material and said blank for conjointuniversal movements relative to a cutting tool associated with saidblank and to a follower associated with said material moving said blankand said material relatively to said tool and to said follower to causethe latter to enter a finger opening in said material; and controllingthe relative movements of said cutting tool and said blank in accordancewith the curvature of the openings formed in said material to cutopenings in said blank according to the openings in said material.

2. The method of cutting curved finger openings in a bowling ball blankin accordance with the natural span and curvature of the prospectiveusers fingers, said meth- 0d comprising the steps of forming a mass ofmaterial in a semiplastic state to simulate a bowling ball; insertingthe prospective users fingers in said material to form curved fingeropenings therein; introducing a follower to a selected opening in saidmaterial; presenting a cutting tol to said blank; effecting conjoint,universal movement of said material and said blank relative to saidfollower and said cutting tool to cause said follower to follow thecurvature of said selected opening in said material; and relativelymoving said cutting tool and said blank in accordance with the followingmovements of said follower to cut in said blank an opening correspondingto said selected opening in said material.

3. The method of cutting curved finger openings in a bowling ball blankin accordance with the natural span and curvature of the prospectiveusers iingers., said method comprising the steps of forming a mass ofmaterial in a semiplastic state to simulate a bowling ball; insertingthe prospective users ngers in said material to form a number of curvedfinger openings therein; introducing a follower to a selected opening insaid material; presenting a cutting tool to said blank; effectinguniversal conjoint movement of said material and said blank relative tosaid follower and said cuttingtool to cause said follower to 10 inaccordance with the following movements of said follower to cut in saidblank an opening corresponding to said selected opening in saidmaterial; and repeating said steps for the cutting of each of theremaining openings to 5l be formed in said blank.

References Cited in the file of this patent UNITED STATES PATENTSSterczek July 5, 1955 FOREIGN PATENTS 636,727 y Germany oer. 14, 1936

1. THE METHOD OF CUTTING CURVED FINGER OPENINGS IN A BOWLING BALL BLANKIN ACCORDANCE WITH THE NATURAL SPAN AND CURVATURE OF THE PROSPECTIVEUSER''S FINGERS, SAID METHOD COMPRISING THE STEPS OF FORMING A MASS OFMATERIAL IN A SEMIPLASTIC STATE TO SIMULATE A BOWLING BALL; INSERTINGTHE PROSPECTIVE USER''S FINGERS IN SAID MATERIAL TO FORM CURVED FINGEROPENINGS THEREIN; MOUNTING SAID MATERIAL AND SAID BLANK FOR CONJOINTUNIVERSAL MOVEMENTS RELATIVE TO A CUTTING TOOL ASSOCIATED WITH SAIDBLANK AND TO A FOLLOWER ASSOCIATED WITH SAID MATERIAL MOVING SAID BLANKAND SAID MATERIAL RELATIVELY TO SAID TOOL AND TO SAID FOLLOWER TO CAUSETHE LATTER TO ENTER A FINGER OPENING IN SAID